One week ago, my Linux NAS decided to spam me with mails, while I was sitting in a bar. Nothing is more disturbing, while having a nice chat and drink a beer, than your home server screaming about a failed RAID. I have to admit, I knew the RAID will fail soon, since one of the HDDs already was marked bad by SMART for some weeks…

Anyway, I shut down the server remotely and ordered immediately two new Seagate 4 TB NAS Drives. They arrived soon, but then my struggle begun. I really had no idea how to replace the HDDs in the RAID array and then grow the RAID to the new size of the HDDs, since my old drives where only 2 TB.

After some time of Google research I was aware of the steps to perform the procedure and it’s fairly easy!

(Be aware that identifier in your system might be different! Perform this steps at your own risk and make a backup before you perform anything on your system!)

Shutdown the server and replace the failed HDD with the first new HDD.

Now its time to create a new partition on the drive. Since my partition will be greater than 2 TB, I need to use GPT layout on the drive. This can be archived with the parted command.

Recently my cable modem refused to connect to my provider, stating “Connection Refused”. The provider (UPC Austria) stated, that they have to come to my place and make some measurements. But this will be in one week…. WTF?? One week without internet? No way!

Fortunately, my provider offers a service, that every router provides two networks, a private one for the single customer, and a free network for all customers of UPC. This “UPC Wi-Free” was also available from some neighbours of mine.

It would be easy to connect all of my PCs to the network, but this is not enough for me. I needed a better solution. Also the PC of my girlfriend refused to connect to this network, my big PC has no WiFi and the server for sure not. Also the chromecast and the firestick…. no I will not configure all devices to configure them later again!

My previous setup included the router from my provider connected to my own router, a Fritz Box. All my devices are then behind the Fritz Box. So the only thing I had to change was to replace the UPC router with my Raspberry PI.

My starting point was the following:

Raspberry PI 2B

Alfa AWUS036H Wifi Adapter

a network cable 🙂

First I powered up the Raspberry and was curious what I had done with this firmware before. Apparently, I used it before for some photographing stuff… 🙂 Anyway, first the Debian needed to be updated from 7 (wheezy) to 8 (jessie).

This took a while, the raspi is not a fast gaming machine… After the upgrade, I configured the WiFi adapter to work with the UPC Wi-Free. For this the wpa_supplicant and the the network interfaces have to be configured:

The following content belongs to /etc/wpa_supplicant/wpa_supplicant.conf:

Shell

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network={

ssid="UPC Wi-Free"

scan_ssid=1

key_mgmt=WPA-EAP

eap=PEAP

identity="your@e.mail"

password="password"

phase1="peaplabel=0"

phase2="auth=MSCHAPV2"

}

And this belongs to /etc/network/interfaces:

Shell

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auto lo

iface lo inet loopback

# give the ethernet a static ip for acting as DHCP Server

auto eth0

allow-hotplug eth0

iface eth0 inet static

address192.168.1.1

netmask255.255.255.0

dns-nameservers8.8.8.8

# configure the WiFi interface and enable auto start

auto wlan0

allow-hotplug wlan0

iface wlan0 inet manual

wpa-roam/etc/wpa_supplicant/wpa_supplicant.conf

iface defaultinet dhcp

You can use different IPs for sure and also you can specify any other DNS than Googles 8.8.8.8. Now we restart the network service and test the connection:

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sudo service networking restart

ping google.de

PING google.de(173.194.116.111)56(84)bytes of data.

64bytes from fra02s27-in-f15.1e100.net(173.194.116.111):icmp_seq=1ttl=55time=23.2ms

64bytes from fra02s27-in-f15.1e100.net(173.194.116.111):icmp_seq=2ttl=55time=35.2ms

64bytes from fra02s27-in-f15.1e100.net(173.194.116.111):icmp_seq=3ttl=55time=30.6ms

The Ethernet interface need a static IP in order to serve DHCP. For this we need also a DHCP server installed on the raspi. We achieve this with the ISC DHCP Server.

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sudo apt-getinstall isc-dhcp-server

We need then to configure the server with a really basic configuration. The configuration is done by editing the file /etc/dhcp/dhcpd.conf.

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default-lease-time600;

max-lease-time7200;

authoritative;

log-facility local7;

subnet192.168.1.0netmask255.255.255.0{

range192.168.1.201192.168.1.250;

option routers192.168.1.1;

}

Basically the set here some lease times for the server, with authoritative we tell the server that he will server this range alone. Later we define a small subnet. The “option routers” is important, because here the DHCP server will tell clients that he will also serve requests later as the gateway.

Now we can start the server:

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sudo service isc-dhcp-server restart

Now we can connect the router and we will see that the raspi serves with an IP address. Now we have to connect both interfaces. In my case the interfaces have the names eth0 and wlan0. We use iptables for this:

All these years I wanted to buy myself a slider for time lapses. All these years they where to expensive for me. The good ones like the Stage One from http://www.dynamicperception.com/ will cost you, depending on the configuration up to $1,250.00. Without shipping to Europe. Even the small ones like the Rhino Slider EVO Carbon are at least $500, again without shipping. So I decided to build my own.

I ordered some aluminum pipes, a aluminum plate, four teflon bearings, two aluminum blocks and used a 3D printer for some other parts. After some time of sticking, milling, drilling and printing, this is the outcome.

EDIT: Dropbox recently closed the public folder system where I store my camera database. Therefor the app was crashing while updating the database. I fixed this issue and the new version 1.3.0 is going live now.

Due to the overall great response and the high number of mails from users of my Shutter Speed Calculator i’m glad to announce here: Night Fox – Shutter Speed Calculator for Android!

The App features a simple interface to input your camera, your focal length and the tolerance in pixels. After that you can simply hit the calculate button and read the suggested speeds.

If you cannot find your camera in the list, simply write me an email or leave a comment. I can add cameras live and you just have to hit the “Download Camera File” Button to load the newest definition data. If you enjoy the app, please leave a comment and help me improve the interface and the user experience!

Thanks to my friend Marcus, i was able to shoot some nice pictures from the moon eclipse today in the morning. Additionally it was also a Blood Super Moon! This happens pretty rarely and the next time will be 2033.

Some months ago I posted that i’m building my own LED ring in order to get some nice closeup shots and have something special for portraits. The project was on hold for some time, but I got back to it, and now I have my first working prototype. Here two picture of flowers I took with the ring and my 17-40 mm.

Here I have also some shots of the ring itself. I already have some ideas of improvement. The mayor problem is that the ring is very long and on my 17-40 mm I can see the ring at 17-19 mm. Also I’ll go for SMD power LEDs to get even more light. Also a connection to the camera is mandatory. Maybe I’ll think of a E-TTL connection via a small micro controller.

Update2: Because of the massive amount of traffic I received I had to disable the live measurement and block some IPs who where causing my server to slow down…

Update: Here are the measurements from the 20. of March, the day of the solar eclipse. And as you can see the grid operators were well prepared. The frequency was actually less fluctuating than the days before.

Today I decided to take again online my grid frequency measurement unit. In some days there will be a solar eclipse in Europe and maybe we will notice a slight fluctuation of the frequency during the eclipse. If it will be a sunny day, the shadow of the moon will race over the ground and will switch of the PV plants in Europe. The installed PV generation in Europe is according to this LINK 81,5 GW. But the overall installed power is more that 1300 GW. So a black out will not happen.

But so far, have fun:

Background:

The grid frequency is a very important measurement factor of the grid. In the electric grid, the balance between generation and demand, due to the lack of a high number of storage, have to be equal at every time. The frequency is a performance indicator in which state this balance is. Lower than 50 Hz the generation is less than the demand, and vice versa. The frequency is therefore used to adapt the power output of power plants to the demand.

Today I installed reCAPTCHA to get rid of spam. The installation was really simple and I noticed really fast that my IP Blacklist plugin had a little time to relax. But I noticed that the login page look a bit odd. I googled a bit but didn’t find anybody whit the same problem. Also nobody answered in the google group about my question. So I researched myself and found the wordpress tutorial to change your login page.

I added the following to my functions.php, just to increase the size of the login page to 400px, and voila, better.

UPDATE 3: recently 500px changed the website and you cannot see the number of likes anymore…

UPDATE 2: Now i’m continuing the test, but this time with an another account and a new picture. I’ll now wait the whole 24 hours period of 500px and upload only once a day.

Test Uploads, Score of the Picture according to 500px Pulse and the absolute Views/Likes/Favorites

Date/Time

8 am

10 am

12 am

2 pm

4 pm

6 pm

8 pm

10 pm

12 pm

2 am

Monday

88.2
166/-/22

88.9
170/27/4

88
199/27/9

90.5
197/32/8

85.1
33/19/3

Tuesday

88.3
213/22/10

90.6
219/31/7

63,9
42/5/2

Wednesday

91.3
363/34/9

89.7
146/25/11

56,6
12/4/1

Thursday

87.7
393/23/6

87.1
123/21/8

iP

93.0
530/43/11

Friday

Saturday

Sunday

60.1
28/5/1

85.0
97/18/4

UPDATE: I just stopped this test, because I realized, that the users rating is influencing the tests. When I was uploading normally my pictures before, the first Like was worth about 27 Pulse, the second something around 15 and so on. Whit my test is was upload 5-6 times per day the same picture. At the last day, a Like was worth 10 Pulse! With this, my test will deliver really bad results and completely destroy me repetition on 500px. I decided to slow down this test and upload the picture not so often anymore. Maybe I will use the whole 24 hours span of 500px to get the real rating.

I’m not completely sure how the algorithm works, but according to my findings, a click on Like is not worth 27 Pulse at all time and all users. Below, the rating of three pictures can be seen. (Sorry for German… 🙂 ) All of them have the same Likes and Favorites, but different Rating. All of them are from the “New” section at the same 10 minutes. And all of them had no comments. The first one is mine. It seems that the view to like ratio does not influence the rating that much, since the third picture hat more views but a higher score. Whats left over, is the users rating. Correct me if i’m wrong!

Since some time I’m participate on 500px.com, to share my photos and get some feedback on the composition and processing etc. My choice felt to 500px.com because I don’t want to create an Yahoo account, I simply didn’t thought about Tumblr and I hate the iPhone majority on Instagram (yes, I have a rooted Android :P). Anyway, 500px offers with the rating system an interesting way of measure the, let’s say, “Beauty” of your pictures, compositions and processing. Also you can have the pictures still with a CC license (maybe the others have this as well, donno…). After I uploaded some photos I got exited. I was spending nights with watching other photos, like them and post some comments. On the other side my pictures get a relatively good rank and some nice comments. But, for high quality critics, go somewhere else. I had some nice rating over 90 and 95 also. 500px has a nice rating system called Pulse. If you want to sell pictures, a high rating, Pulse, is recommended.

When the days got longer, I had some time at the golden hour and blue hour to take some pictures. I also had a new lens and I was still exited with my new 6D. I started photographing at 5 pm and ended at 9 pm or later. After that processing the pictures was not in my mood and I left that for the next day. So i stood up, made some processing and uploaded the pictures, let’s say, between 9:00 and 9:30 (CET) in the morning, three, four days in a row. I was really surprised that the rating where just around 70-80, sometimes less. Could it be that I’m, not like I thought a little bit good, really bad at photographing?

But I was going curious. I noticed also that the count of viewers where not that high like before. OK, no views, no likes, no rating. Even the best pictures of 500px have normally a 1-to-10 rating for “likes” to views and even less with “favorite“. So I made a simply test with one of my pictures. The photo on the right is the DC Tower in Vienna. Not the greatest picture, I know but a 80 worth for sure. The first time i uploaded this picture at around 9-10 AM CET, the pulse stood still after some hours, at around 70. The second time, I uploaded at 8 PM CET. And voilà, the pulse reached 90.7. Also the views where going from some under 100 to over 400. So there are clearly some good and bad times for uploading photos to 500px.

I decided to make a test with one of my newest pictures from Vienna. Also not a very good picture, but clearly worth a 80 or 85. I will upload this picture the next weeks to different time and will not interact with 500px at all, only to see the rating and the views after 2 hours and the upload to a different time again. I started today again at 9:30 AM CET. I’ll try to update this post recently to the latest results as soon as possible.

Test Uploads, Score of the Picture according to 500px Pulse and the absolute views